Well head equipment for wells with multiple pipe strings



April 9, 1957 c. 0. BROWN 2,788,074

wsu. HEAD EQUIPMENT FOR WELLS WITH MULTIPLE PIPE STRINGS Filed July 6, 1953 C. C. Brown INVENTOR.

A TTORNE y WELL HEAD EQUIPMENT FOR WELLS WITH MULTIPLE PIPE STRINGS Cicero C. Brown, Houston, Tex. Application July 6, 1953, Serial No. 366,343 6 Claims. Cl. 166-78) This invention relates to improvements in well head equipment as particularly employed on oil and gas wells.

In the operation of a well equipped with the conventional casing and tubing head construction, the tubing head supporting an inner pipe string within the well casing, it will often be necessaryto rotate the inner pipe string, that is, the tubing string, in order to manipulate various pieces of equipment'which are mounted on the tubing string and are located below'the top of the well inside the casing. Such pieces of equipment which are thus manipulated may include packers, testing tools, anchors, and the like.

In conventional well head constructions, when it becomes necessary or desirable to rotate the inner pipe string, the connections to the lateral branch pipes must be broken, as well as the connections between the tubing head and the casing head, in order to permit thedesired rotary movement of the inner string relative to the outer string. This not only requires considerable eifort and expenditure of time but is hazardous to the well and to the personnel working about the well because breaking of the connections between the heads and the lateral connections exposes the Well to loss of control of high pressure fluids in the well which might suddenly'be released and cause dangerous blow-outs.

tion to provide an improved well head construction which will obviate the disadvantages of the more conventional well head constructions as described.

'An importantobjectis to provide an improved well head construction which will readily permit rotationof an inner pipe string relative to an outer pipe string without-requiring the breaking or releasing of any of the several connections between the respective heads and between the heads and the several lateral branches.

A more specific object is to provide a swivel connection between a casing head and a tubing head whereby the string of tubing connected to the tubing head may be rotated in the tubing head relative to the casing head without disturbing the lateral branch connections to the tubing head.

A h w iss "is -w-Pr imbu1- r poo onnected to the upper end of the tubing string-and mounted to swivel in the casing head and being arranged to swivel (the tubing head'above the casing head.

LOQther and-more specific"object s and advantages will becomeiapparent from the following detailed description when", r'eadjin conjunction'witli tne'aceempan ing' dr wing which illustrates eneus'e'farenibeairhehtin accordance with the present invention by which the various objects and advantages of this invention may be successfully accomplished.

In the drawing:

Fig. 1 is an elevational view, partly in section, showing the improved device in accordance with this invention incorporated in a well Christmas tree; and

, nited States Patent l Accordingly, it is a primary object of the present Fig. 2 is an enlarged longitudinalsectional view of detail of the construction illustrated in Fig. 1.

In the drawing, there is shown the upper portion of a conventional tubular casing head 1 having an axial bore, 2 and also having the usual annular laterallyv extending bolt flange 3. It will be understood that the lower end of easing head 1 (not shown) will be mounted in the. usual manner on the upper end of a conventional well easing (not shown) of relatively large diameter which- EX-, tending coaxially through bore 2 is a string of smaller diameter pipe, such as the tubing string 4, the upper extends into a well bore from the ground surface.

end of which projects slightly above the upper end of easing head 1. The upper end of bore 2 is counterbored at 5 to form an upwardly facing annular seat 6. The upper end of counterbore 5 runs out into the upper end;

of flange 3 in a bevelled surface 7.

The upper end of tubing string 4 is provided with ex ternal threads 8 adapted to threadedly receive the lower. end of a tubular nipple 9 which extends into counterbo're- 5 between the exterior of tubing 4 and the wall of the; counterbore to a point vertically spaced from seat 6.{ The lower end of nipple 9 terminates in a downwardlyfacing annular seating surface 10. The space between seat 6 and seating surface 10 is adapted to receive ball bearings 11 mounted between races 1212 by means of which a swivel connection is provided between tubing 4 and easing head 1.. The outer surface of nipple 9 is suit-- ably machined or formed to provide a bevelled seat I3; opposite bevelled surface 7 and tapering oppositely to;

the latter to form therewith a V-shaped notch between the wall of counterbore 5 and the exterior of nipple 9,

this notch being adapted to receive an inverted U-shaped,

packing ring 14 to seal the space between the wall of counterbore 5 and nipple 9. An annular bolt flange 15,.

is mounted about the exterior of nipple 9 and hasan axial bore 16 in which nipple 9 is freely rotatable, ,Aj plurality of studs 17 extend through holes 18in flange 15 and screw into registering threadedholes 19, in flanges 3 whereby flange 15 may be tightly secured to casingv head 1, the tightening of studs 17 serving to compress, packing ring 14 and to hold nipple 9 down in the bore;

of casinghead 1. With the arrangement thus fardescribed, it will be seen that nipple 9 and tubing 4 may freely swivel in casing head 1, seat 6 serving to support the weight of the tubing string and other elements mounted thereon as will subsequentlyv be described.

tubing string 4.

Secured to the upper end of flange 23 of master 22 is a tubular sleeve 25, provided about its lower end;-

with a bolt flange 26 by which sleeve 25 is secured to flange 23 by means of bolts 27, sleeve 25 being thus vertically positioned and co-axially alignedwith the tubing string; Surrounding sleeve 25 is a tubing head structure: designated generally bythe-numeral 28., and comprisin'g' a generally tubular body 29" having an'axial bore} which sleeve 25"will be readily rotatable. Body 29' is bio-' vided intermediate its opposite ends with a plurality of radial passages 31 providing communication between bore 30 and the exterior of the body, the surfaces of the latter about the outer ends of passages 31 being annularly flattened to provide seating surfaces 32-32 for attachment of the flanged ends 33 of lateral branch conduits 34 Patented Apr; 9, I 1957.

which communicate with passages 31, flanged ends 33 being secured to surfaces 32 by means of studs 35. Passages 31 may be internally threaded at 36 to receive screw connections to branch conduits 34 instead of the flanged connections shown. The wallv of sleeve 25 is pierced by a plurality of angularly spaced ports 37 adapted to register with passages 31 at various angular positions of sleeve 25 whereby to provide communication between the bore of sleeve 25 and passages 31. Bore 30 of body 29 is counterbored from its opposite ends to form annular stuffing boxes 38-38 terminating at their inner ends above and below passagesdl. Compressible packings 39 are seated in the stufiing boxes whereby to provide fluid-tight seals between body 29 and sleeve 25 while permitting rotation of the latter relative to body 29. Annular packing glands 4040 are inserted'in stufiing boxes 38-48 in axial compressive relation to the respective packings and are provided at. their outer ends with outwardly projecting annular lips 41-41. The'lip 41 on the lower gland projects between the end of the hub of flange 26 and the adjacent lower end of body 29; The lip 41 on the upper gland projects over the upper end of body 29 and is urged downwardly by the lower end of a collar 42 which is screwed down overthe upper end of sleeve 25 which is: externally threaded at 43 to receive collar 42. it will be seen that as collar 42 is screwed down. on sleeve 25 it will bear against the outer end of upper gland 40 and 40, the. reaction of which, through its abutting engagement with the hub of flange 26, will compress lower packirrg 39. Theupper end of collar 42 is closed by means of a metal plug 44 having a transverse hole 45 therethrough for the reception of a wrench bar or other turning tool (not shown).

When it is desired to rotate tubing string 4, with the above-described arrangement, it is only necessary to in.- sert a suitable wrench bar or turning tool into opening 45 to serve as a handle by which sleeve 25 may be rotated relative to body 29. Rotation of sleeve 25 will act through its connection to valve 22. and nipple 9 to rotate tubing string; in, casing headv 1. It: willlbe seen that this rotational movement may be eifected without in any way disturbing the external connections to casing head 1 and tubing head 28. The ports 37 will maintain communication between the interior of tubing string 4 and lateral branches 34 and fluid flowing through tubing string 4 will remain fully under the control of master val 2.2-

It will be obvious that master valve22 may be eliminated from the connection between sleeve 25 and nipple 9, if desired, without altering the rotary function of the device. In such modification, nipple 9 is provided at its upper endvwith internal threads 46 into which the lower externally threaded end 47 of sleeve 25 may be screwed. Flanges 21 and 26 would thus also be eliminated and lip 41 of the lower gland 40 would rest on the upper. end face of nipple 9.

It will be understood that numerous alterations: and, modifications may be made in the details of the illustralive embodiment within the scope oi the appended claims but without departing fromthe spirit of this invention.

What I claim and desire to secure by Letters Patent is:

. 1, In a well equipped with concentric inner and outer pipe strings, the outer pipe string havingmounted on they the inner pipe string in which the inner pipe string is rotatable, comprising, a generally tubular body mounted on said portion above said casing head in vertically spaced relation to the upper end thereof and having a through bore co-axial with the inner pipe string to rotatably receive the upwardly projecting portion of said inner pipe string, radial passages through the wall of said body communicating with said bore, swivel means in said casing headarranged to rotatab ly support said inner pipe string therein, means closing the upper end of said portion, port means positioned in said portion to maintain communication between said radial passages and the interior of the inner pipe string during rotation of the latter relative to said body, and sealing means disposed in said body to seal about said portion above and below said passages.

2. In a structure according to claim 1, a block valve interposed in said upwardly-projecting portion between said body and said casing head.

3. A structure according to claim 1, wherein said upwardly-projecting portion comprises a tubular sleeve member separably connected to the upper end of said inner pipe string.

4. A. structure according, to claim 1, wherein said swivel connection. comprises a downwardly facing external annularshoulder on said inner pipe string, a cooperating upwardly facing internal annular shoulder in the bore of the casing head and anti-friction bearing means disposed between said shoulders.

5. In a structure according to claim 1, annular sealing means positioned to seal the annular space between said well head fitting and the exterior of said pipe string above said swivel means.

6. In a well equipped with concentric inner and outer pipostrings, the outer. pipe string having mounted on the upper end thereof a generally tubular casing head and said inner pipe 'stringj having a portion projecting upwardly through said casing head, a tubing head structure for the innerrst'ring in which the inner pipe string is rotatable, comprising, a generally tubular body mounted on said portion above said casing head in vertically spaced relation to the upper endthereof and having a bore coaxial with the ihner pipe string to rotatably receive said upwardly projecting portion, said upwardly projecting portion comprising a tubular sleeve member separably connected to the upper. end of the inner pipe string and extending entirely through the bore of said tubular body, swivel means in said casing head arranged to rotatably support the inner pipe string therein,.a block valve interposed in said'upwardly projecting portion at a point between said body and said casing head, radial passages through the wall of said body communicating with said bore, means, closing the upper end of said sleeve member, port means positioned in the sleeve member to maintain communication between said radial passages and the interior of'the inner pipe string during rotation of the latter relative to said body, and sealing means disposed in said body to seal aboutsaid sleeve member above and below said passages.

References'Clted' in the file of this patent UNITED STATES PATENTS Baker. n June 3, 1952 

